...

cxx/mount_astrom.h

@@ -8,7 +8,10 @@
 
 #include <chrono>
 #include <fstream>
+
+#ifdef VEC_XSIMD
 #include <xsimd/xsimd.hpp>
+#endif
 
 #include "mcc_traits.h"
 #include "mount_astrom_default.h"
@@ -23,9 +26,10 @@ namespace erfa
 namespace mcc::traits
 {
 
+#ifdef VEC_XSIMD
 template <typename T>
 concept mcc_scalar_or_simd_c = xsimd::is_batch<T>::value || std::is_arithmetic_v<T>;
-
+#endif
 
 template <typename T>
 concept mcc_real_scalar_or_real_range_c =